PhysX cloth physics are used throughout Witcher 3, such as on the many flags on this battlefield.

If you've read my main PhysX article, you'll already know that a dedicated PhysX card is generally a good idea, frequently providing a 15-30% framerate boost, and reducing stuttering to boot. But how does it fare in Witcher 3?

Despite falling short of some expectations (I'm particularly disappointed by the environment texture quality), Witcher 3 is still without a doubt one of the best-looking games ever made. The detail is dense, the art design is magnificent, and there's an impressive amount of physics on display.

When it comes to hair, Witcher 3 is in a class of its own. Think Tomb Raider's TressFX but less showy, and applied more frequently. Geralt's hair is simply the most natural-looking hair you've ever seen in a game, and the fur on some of the creatures is just fantastic. Of course, all this hair (up to 125,000 strands on-screen at a time, apparently!) comes at a performance cost, and unfortunately, it doesn't use PhysX. Witcher 3's hair physics uses Nvidia HairWorks, which uses your main GPU only.

Witcher 3 doesn't use PhysX for hair, but it does use it for cloth and destruction effects. These effects are used on all platforms (consoles too), and are said to use the CPU. However, I can confirm that they do utilise my dedicated PhysX card.....though not much - the most I saw was about 9% usage.

Shut up and test

I went to areas where there were a lot of PhysX enabled objects (flags, banners, hanging herbs, etc.) and tested the framerate both while standing still, and while using the Aard sign to fling everything about. I then averaged the results below.

Without dedicated PhysX card: 50.1With dedicated PhysX card: 50.8

Yup. Not very impressive at all. I'll add that I don't think the 0.7fps is mere statistical noise. I really did notice a ~1 fps difference in most of the areas I tested in, especially when throwing Aard. But 1fps is 1fps, so who cares, right?

I'll also add a caveat: I'm not very far into the game. It's entirely possible that there are some areas I haven't seen that are much more demanding for PhysX (This happens very often in PhysX-enabled games). It's also entirely possible that with a levelled up Geralt who possess a much stronger Aard, I'd see much larger and more taxing destruction PhysX effects . So, while I'm not flipping somersaults about my 0.7fps increase, I am at least content to know that my PhysX card will be ready to absorb anything the game might throw at it later on.

So the upshot is this: Witcher 3 ain't no Metro: Last Light. If you already have a PhysX card, keep it in - who knows, it may save you the occasional minor slowdown. But if you don't, don't go buying one just for Witcher 3.

Hi just a quick question about your test. It says your running 2 titan sli and the 650ti for physx. All that is set with your 4770k. The 4770k only has 16 pcie lanes max.

Witcher 3 is known to run upwards to 25% bus usage @ 16x pcie3.0 or 50% bus usage on a 8x pcie3.0 slot single gpu use. When your enable gpu SLI, Bandwidth overhead does increase slightly. Is it possible that you've effectively Bottleneck 1 of your Titan Gpus? I ask this because a 4x pcie3.0 can be easily capped by bandwidth from a titan. Just saying food for thought

I'm not sure if I've understood your question. But my motherboard has a PLX chip and is specified to be able to handle x8 pcie3.0 on all 3 of my cards.

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Random internet dude number 2

1/2/2016 07:23:43 am

your mother board may be able to handle that but your cpu itself can not. Your motherboard is only able up to that while your cpu can only handle 16 total pcie 3.0 lanes.

Adam

8/3/2015 06:50:44 am

This benchmark doesn't make sense. Yes, The Witcher 3 does have physx support. However, it is CPU-accelerated. It doesn't matter whether you install a physx card or not, this game won't use it.
Borderlands 2 for example benefits greatly from a dedicated physx card.